Answer:
13
Step-by-step explanation:
(11x - 15) + (5x - 13) = 180 (Since a straight line = 180°)
11x + 5x - 15 - 13 = 180 (Combine like terms)
16x - 28 = 180 (Simplify)
16x - 28 + 28 = 180 + 28 (Add 28 to both sides)
16x = 208 (Simplify)
16x ÷ 16 = 208 ÷ 16 (Divide both sides by 16)
x = 13 (Simplify)
